I started looking at poly hives a couple of years ago. It started as I had a mish mash of wooden hives and I wanted to head to one type. I also wanted to go for one size box as brood and supers.
At the time I knew that I wanted to expand in numbers so I started looking around. As we all know ask 10 beekeepers a question and you can get 14 differing answers in how to look after your bee's or which is the best hive. When I also started in TBH's it is surprising how many can poo poo the idea having never tried it.
Anyhow, when you look round the internet there are a few different poly hives types and styles. So I settled for a Langstroth Poly. Some supplier quality seems to vary but eventually found the one I settled with.
I bought one as a trial and ran it alongside wooden commercials and nationals. They did seem to fair better overwinter than the wood, but not a lot in it. I can not comment on honey production as I had them working hard on drawing wax out on frames and winter stores.
I have found no real cons at this stage. The only grumble I could think off was the 'green' credentials of wood over poly. That said if you read the manufacturers blurb they will give you there believed figures on oil used to manufacture and how to recycle. That said ply is not always as 'green' as you think it is and cedar can be imported and that can negate its green credentials somewhat.
the only other issue that I was a little concerned with is the cleaning of them. However the national bee unit provides advice on that for poly hives as do the manufacturers.
Oh and nearly forgot, you do have to be a little careful about handling as they do get damaged if you bang them and drop them, but then so do wooden ones.
for me the pro's.
Poly hives have been used for 30+ years now so they cant be all that bad,
Commercial bee farmers use them, if they are doing it as a business again it can not be that bad.
Cheaper which was a big consideration especially when I want to get up into double figures of hive numbers.
They are lighter, which is useful when running an all brood box system, saves the back just a little.
Over winter the cluster seemed more content to move around the stores than they did in the wooden ones.
I only ran both for a year and half so not really long enough to directly compare the two in true research style.
However I have now switched and won't go back to wood.
With regards to condensation, I have not had any problems with that, they do have good ventilation as I run with OMF's open all year round on the hives.
I am now also trialling plastic foundation to go with them. So will see how that goes.
Any questions?
Steve